The present invention is directed to electric and hybrid electric off-road and on-road vehicles, which use solely a battery pack or a battery and electric generating system to supply energy for propulsion. Such battery packs include multiple battery modules connected in series or parallel. The invention addresses a variety of environmental and technical challenges associated with reliable and long-term battery operation. Vehicles utilizing the invention include electric and hybrid electric buses, trucks, material handling vehicles (forklifts and pallet jacks), neighborhood electric vehicles, and airport support equipment.